This invention relates to a thermal transfer recording medium which can be used for multiple times. More particularly, the present invention pertains to a thermal transfer recording medium by which transferred images with constant transfer density can be obtained with an application energy at a certain level or higher and constant printed letter quality can be obtained for multiple times without being influenced by the subtle change in the application energy.
As the thermal transfer recording medium to be used for multiple times, for example, Japanese Provisional Patent Publication No. 105579/1980 discloses a technique in which a microporous layer is formed with a resin and the layer is impregnated with ink. Also, Japanese Provisional Patent Publication No. 160691/1982 discloses a technique, in which a reticulate structure is formed with the use of organic or inorganic fine powder and impregnated with ink. Further, Japanese Provisional Patent Publication No. 185192/1982 discloses a technique in which a porous paper is impregnated with ink.
All of these techniques are elaborated to permit ink to be oozed out little by little through a porous material, but these involve the problem that the transfer density is changed corresponding to subtle change in application energy, whereby no constant printing letter quality can be obtained.